iapnupdatetfdata.straighttalk.con

I have a factory unlocked i-phone 4s and I am using a Straight Talk sim card. This has worked well for several months. Last week I started having trouble with my 4G connection. I called Apple and they walked me through re-setting the Network settings. The 4G connection worked great, except I could no longer send or receive mms messages. My data network tab is not on the phone. Apple said that it was my carrier but after speaking with Straight Talk I was told that the problem was with my phone. I took my phone to the Apple store and they ran diagnostics and could not find a problem. A friend with the same phone, except they have an AT&T sim card, put her sim card in my phone and once again, the mms messages did not work. Any suggestions

ok Im sure this has been discussed over and over but please help...I called apple today to buy a 3G and the guy literally talked me out of it and listed numerous problems with the 3G and said I should stick with the OG, so now Im very confused...I have iPhone Original, but I want a 3G.... Should I buy a 3G or just stick with the OG?Could I get some pros & cons please, I would love to hear from owners who have experienced both if possible.I know I could probably search and find lots of facts but I want the most current info, and Im on the Edge on my iPhone and its so slow it would take me days to search anything... Sony VAIO Windows XP iPhone 16gb / iPod Video 30gb / iPod Shuffle 1g